Method of and apparatus for refrigeration



June 25, 1929;

W. H. CARRIER METHOD OF AND APPARATUS FOR. REFRIGERATION 2 Sheets-Sheet 1 Filed Aug. 21, 1924 Ill/I 0, HAW K .0 0 0 0 0 0 0 0 0 0 o o/Uo 5;

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Z llVl/f/VTUH WILL/5 H. CARR/[R ATTORNEYS June 25, 1929. w. H. CAI R RIE R 1.718.683

METHOD OF AND A PPARQTUS FOR REFRIGERATION Filed Aug. 21, 1924 2 Sheets-Sheet 2 Patented June 25, 1929.

UNITED STA E s PATENT OFFICE.

WILLIS n. cmmztor nsssx rams, new JERSEY, ASSIGNOB 'ro cesarean-liar- .nnnnme coaroan'rron, or NEWARK, nnw mnsnY.

unrnon or sun 'nrrn wrus son nsrmenm'rmm Application filed August 21, 1924. Serial no. 783,296.

This in vrntion relates to an improved methd of rcfrigeration and more particularly to a mcthodof refrigeration in which the liquid rcfrigcmut is automatically rectified during lhc refrigeration operation, and the heat in llu' warm fluid from the'condenser is used for the rectification of the llqllld. re-

frigerant.

he invention further relatesto a refrigoration apparatus adapted to carry out the improvcd refrigeration method. 'lu thi-- refrigeration system dmclosed 1n my copcudiug application. Serial No. 656,-

1512. lilcd Aug. 7, 1923, an uucoudcusod mixfrom impurities such as oil, water, dirt, etc.,

l subjected the liquid refrigerant during the operation of the system to the indirect heating action of warm liquid refrigerant returnin g fromthe condenser.

l have found that the cold liquid refri eraut delivered to the rectifier may be used to advantage as a cooling mediumfor-condens--' ing the refrigerantifvapor from the gaseous paratus.

vapor mixture from the condenser acts to.

impurities by utiliain the warm vapor and gaseous impurities as tie heating medium for the rectifier, thus eliminating the supplementary condenser and simplifying the ap- The heat from the warm gas and rectify the liquid refri erant which in turn acts as the cooling me ium for condensing the refrigerant vapor from non-condensible uupuritles, and one-plece of apparatus serves.

I the double purpose of supplementarv 'condenser and recti er. By using the warm, uncondensed gases and va orsfrom the. conthe latent heat of vaporization, as well as the hen t. of the liquid refrigerant condensed is available for heating-pur oses in rectification, thus insuring a su cient amount of rectification with a comparatively small volume of heating medium. The condensation of the refrigerant vapor in the as mixture is also effected with a smaller an simpler heat exchange'surface than is necessary m awater cooled condenser-as the liquid refrigerant from the evaporator has a lower temperature than the cooling water.

One object of the invention, therefore, is

to improve methods ofrefri respects above indicated. 01: er objects are ation in the to provide 'a'method of refrigeration 1n which 7 the condensation of refrigerant vapors in a mixture of gas and vapor withdrawn from the condenser, accomplishes'the rectification of the liquid refrigerant to separate it as a vapor from non-vaporizahle impurities; also to provide a refrigeration a paratus for carrying out the above metho m which a single piece of apparatus serves the-double purpose of condenser and rectifier; also to provide a method of refrigeration in which a mixturcof gas and vapor is withdrawn from an ascending current of the mixture 1n the main condenser'to effect a preliminary grav-' ity'separation of the con ensible and noncondensible fluids before the subsequent separation there by condensation in the rectifier; also to provide a. practical method of, and reliable and sensitive apparatus for automatically maintaining a substantially uniform rate of rectification re rdless of the purityof the liquid in the rectifier; and also to impmve refrigeration methods and up I" ratus in'other respects hereinafter descrl ed and set forth in the claims. 4

In the accompanying drawings: Fig. 1 is a diagrammatic plan view of a re-. frigeration apparatus embodying my invention. i

Fig. 2 is a vertical sectional view through the condenser of the refrigeration apparatus. Fig. 3 is a fra ntary sectional elevation showin'g thefevapo ator and the improved rectifier-condenser.

Fig. 4 is a view showing the rectifier in elevation and a fragmentary sectional eleva tion of the evaporator.

Fig. L is a central sectional view of the vapor check valve for the rectifier-condenser. denser as the heating me ium in the. rectifier,

Fig. 6 is a vertical sectional view'of the-regulating valve for the rectifier-condenser.

Fig. 7 is a sectional view through the reoperating with refrigerants such as ichliiro pressures may be used, such, for example, asbelow atmospheric pressure n the evaporator ethylene etc, under vacuum both the evaporator A and in the condenser B but other A and above atmospheric pressure in the condenser B and other refri erants may also be used. The vapors of t e refrigerant are withdrawn from the evaporator A byja com-.

pressor C-of an suitable construction, but

preferabl centrifugal in ty' From the compressor C tliz vaporsofthe refrigerant, including any air or othernoncondensible gases which occur in the refrig- 1 .e'rant as impurities, are. delivered into -the condenser B through an inlet pipe" 10 at a pressurepreferably, but not necessaril below one, atmosphere, The condensib e re- --fr igerant vapors are'condensed by means of water at normal temperatures or other suitable condensing medium which is. circulated through suitab e tubes 11 arranged in the condense? casing 12. Preferably the condensin water enters through an inlet pipe 13 at t e top of the condenser, flows back and forth through successive 'r'oupsof-tubes 11, and leaves throu h an out et pipe, not, shown,

1 at the-bottom o the condenser, as that the flow of water through said't lb s is ina counter-icurrent direction to theflow of the dens estvapor in'thec'on denser' aswill be further explained ,presentlyShitable bafiies. or walls 14: and 15 arranged in th'e condenser casing, cause the'refrigerant vapor entering the condenser tOifilSt pass downwardly over a portion of the coolin tubes, then under the afiie 15, and upwar ly over the remaining tubes in the ascendingpassage formed by said bafile' 15, so-that the densest vapor, to,-

gether with any-'air'or other gaseous impurities which may be present, must rise in said passage to reach an outlet at the top thereof through which the vapor and ases are with-' drawn from thejcondenser. heanixture of air and'wapor in the proportion of about 95% vapor to 5% air, is, lighter than the vapor alone so that during the ascent of'the vapor and gases gravity tends to separate the dense refrigerantyapor from the air with the re:

asaturator or device 16, disclosed in m 7 aforesaid .a plication for the purpose ofsaturating an coolin the vapor entering the condenser and partially relievingthe work off the, condenser, Thefhqillofiedrefrigerant is caused to discharge throughthe saturator-.or-'device 16 through which the refrigerant vapor is delivered from m the condenser main condenserjthrough out 'plained in my-said applicationi In my above mentioned application, a sup-,

ba es 14 and 15 becausev thecompressorinto the condenser: This urator is. constructed and operates as describedin said applicatiom The cooled .;liq-2-;.:=.1f;

aid from the condenser meetingjthe warm vapor fromthe compressor flowing through the. -saturator passage '16, cools-and saturates the vapor so that when'the vapor reaches the QOII- densing tubes of the condenserit ,is already cooled and condensed to some extent, and to.--

that extent relieves the work of the condenser.

The liquefied refrigerantpasses from t he trapped back tO -the evaporator A, as erlementary water cooled condenser isilocated 1n the upperportion of the ascending passage in. the condenser casing ,12 folcondensing and separating the-densest portion of therefrigerant vapor'from the air'or other gaseous impurities. Iyhave found, however, that this condensation eiicctcan be obtained to advantage and said supplementary condenser dispensed with by employing therectifier of the present inventionwhichutilize-s the cool r'e-. fri erant liquid from theevaporator as the coo ing mediunn This liquid refrigerant has alower temperature than water at'nornial temperatures and, therefore, .a' smaller heat exchange surface and onc'of siinplei construction is possible for the same condensationefi'ect, andrat the same time the heat'in the .gases from the condenser is used {or rectification of the refrigerant liquid and the separation of said refrigerant as avapor from non-volatile liquid impurities such as. oil,

water, etc.,c'ontainedtL-erei n.

A vapor outlet pipe 23 connects with the upper end of .theascending passage of the condenser B for the purpose of witlu'li-awing the uncondenscd refrigerant vapors and gase ous impurities therefrom by means-of suitable evacuation mechanism, such, for cx'aii'iple, as

disclosed in my above mentioned application, sa d mechanism comprising an air and vapor se aratmg chamber 24 positioned on theside o the evaporator casing and a motor 25 10-- cated on the top of said chamber whichactuates aumpoto' circulate refrigerant liquid throng an ejector andvscparator in said chamber. The "pipe 23 connects with said ejectorfwhich acts to withdraw the vapor and gaseous impurities .from the condenser throu h the pipe 23. The uncondensed air and ot er gaseous impurities are discharged into. the atmosphere from the separating chamber 24 through a. discharge pipe 26 and the liquid refrigerant, which is condensed and" separated in said chamber 24 is returned to the evaporatorby a suitable mechanism, all as more fully describedin said application.

An other suitable airevacuating and separatmg meanscould be displayed. Between the condenser casing 12 and the separating chamber 24'the pipe 23 is formed into orsuitably connected with a condensing coil or device 27 which is contained in or otherwise suitably arranged to heat a rectifier chamber 28 preferably, but not necessarily, cylindrical in form and having a cover 29.

:A check valve D is located in the line 23, preferably between the condenser casing 12 and the rectifier chamber 28 so that said line is l closed when the apparatus is shut down but is opened automaticall when the evacuator motor 25 is started. T is check' valve may be valve D, a bellows diaphragm 34 contracts and a rod 35 between the diaphragm head of any suitable. construction. I'As shown it has a valve member 30 which is ieldingly pressed by a spring actuated punger 31. against a valve seat 32. When a vacuum is created in the suction port .33 of the check charged therefrom through an outlet pipe 40. "A chamber 41 is formed in the evaporator casing 38, above the tubes 39, and the refrigerant liquid is returned from the condenser to this chamber to be evaporated.

The chamber 41 is provided with a perforated bottom 42 which distributes the liquid refrigerant onto the tubes 39 in numerous small streams. An overflow chamber 44 is formed in the receiving chamber 41 by a wall 45, and an overflow pipe 46 has its upper end located above the bottom of said overflow chamber so that when the refrigeration apparatus. is, operating, a portion of the liquid refrigerant will continuously overflow from the chamber i 44 into thepipe 46.- The ipe 46 delivers the liguid'refrigerant into a unnel 48 at the top a stand pipe 49, said funnel preferably having a wire mesh 50 across its top toprevent 3 the splashing of any dirty liquid out'of stand pipe 49 intothe evaporator casing 38. The stand pipe 49 connects at its bottom with a. pipe 49 which passes out of the evaporator 1 casing 38 and is connected to thebottom of the rectifier-chamber 28. i

Thus the liquid refrigerant rises in the rectifier chamber 28 around theconden'ser coils in said stand pi 27 to a level depending on the head of liquid 49 and. also on the ressure' of the va ors a ove the liquid in said rectifier cham er since, when the pressure in the rectifier chamber 28 reaches a certain point,

the liquid discharging from the pipe '46 will overflow the funnel 48 because of the fact that said stand pipe 49 is full of liquid. A vapor I return pi e 51 connects the upper end of the rectifier c amber 28 with the evaporator casin 38 and is provided with a hand out off va ve 52 of usualconstruction. A restriction device 53 (see Fig. 7) is provided in the vapor pipe 51 being preferably located between the valve 52 and rectifier chamber 28 and consisting of a removable transverse plate 54 in the pipe having an opening55 therethrough for the passage of the vapor. The pressure of vapor in the rectifier chamber 28 depends upon the size of this restriction opening and any desired pressure can be secured by using a plate with an opening of appropriate size.

In the pipe 49 leading from the'stand pipe a sensitive regulatin or check valve 56 is located. This valve is preferably of the following construction. A flexible diaphragm 57 dividing the valve casing into upper and lower chambers, carries a valve seat member 58 through which is a central fluid passage 58. The valve member 59 is provided with a grooved guide stem 60 passing through the as'sage' 58 and is normally held stationary 49 to the bottom of the rectifier chamber 28, 3

etween a stop screw 61 engaging the upper valve member. The valve casing has an inlet port 63 below the diaphragmi57 and a discharge port 64 above said diaphragm. The valve prevents the back flow of any liquid from the rectifier chamber 28, but whenever the head of liquid in the stand pipe 49 becomes suflicient to overcome the pressure of the vapor in the rectifier chamber 28, the diaphragm 57 is deflected upwardly and lifts the valve seat off of the valve allowing liquid to flow from the stand pipe 49 into the recti fier chamber 28. In the event of an abnormend of said stem and a sprlng pressed safety stop screw 62 engaging the lower end of the ally high pressure in the rectifying chamber the safety screw will permit the valve toyield downwardly with the valve seat so as. to prevent injury to the valve or seat while nevertheless holding thevalve closed.

It is desired to cause the liquid refrigerant to be distilled or rectified at a substantially.

uniform rate, notwithstanding variations in its-purity, and the mechanism described is especially. suited for this'purpose. The warm vapors from the condenser B passing-through the condenser coil 27, transfer their heat through the walls of said coil to the liquid refri erant in the rectifier chamber sur rounding said coil, causing said refri erant to boil and to distill ofi' vapors'of t e refregerant which pass through the restriction opening 55 and return pipe 51 into the evaporator casing 38. When operating for a considerable length of time, the liquid in the rectifying chamber 28 becomes more and more bntaminate'd with the impurities, such as oil, water, and the like, containedin the refrigerant so that the evaporation in pounds of refrigerant per unit of condenser coil surface continually decreasesf When the refrigerant liquid is fresh in the rectifier chamber 28 the vapors are given off rapidly and the comparatively high vapor pressure caused in the rectifying chamber by the restriction opening 55 overbalances the head of liquid in the stand pipe 49 and holds the valve 59 closed so'as to maintain the liquid level 65 in the rectifier chamber 28 comparatively low with a smaller portion of the condenser coil 27 in contact with said liquid thus causing a reduction in the rate of evaporation. As the liquid becomes more polluted, the vaporization is less rapid so that the vapor pressure is reduced and permits the valve 59 to open and the liquid to rise higher in'the rectifier chamber 28 because of the head of liquid in the stand pipe 49and thus automatically increase the rate of evaporation from the pollutcd liquid. Therefore the net evaporation or pounds of refrigerant vapor per unit of time passing through the pipe 51 is automatically maintained substantially uniform regardless of the purity of the liquid in said rectifier chamber. The described regulating means for the rectifier are very sensitive. The regulating valve will open and close with small differences in the head of the liquid in the. stand pipe and maintain a substantially uniform action of the rectifier.

When the oil, water or other impurities have accumulated in sufficient quantity in the rectifying chamber, said liquid is drained from the rectifier chamber 28. For this .purpose a drain pipe 66, controlled by a hand valve 67 is provided at the bottom of said rectifier and an air vent pipe 68 having valve 69 is pro vided at the top ofthe rectifier chamber 28. In withdrawing the polluted liquid from the rectifier chamber 28, the vapor outlet valve 52 is first closed, and the vent valve 69 opened which breaks the partial vacuum in the rectifier chamber 28 and indreases the pressure in said chamber so that the regulating valve 56 closes. The drain valve 67 is then opened and the liquid drained out, after which the .valves 67 and 69 are closed and the valve 52 opened, which again puts the device in operation as a combination rectifier and condenser. A gage glass 70 of the usual construction may be connected between the pipe 51 and pipe'49 for indicating the level of the liquid in the rectifier chamber 28 and for also indicating the color or purity of said liquid.

By employing the rectifier as asupplementary condenser for the vapor withdrawn from the main condenser and using cold liquid refrigerant from the evaporator as the cooling medium in the supplementary condenser, the amount of condensing coil surface necessary for the desired amount of condensation is considerably reduced since the temperature of said .liquid refrigerant is considerably less than the normal temperature of cooling water,

so that the condensation is more effective and more complete. On the other hand by using the vapors from the main condenser as a heating medium for the rectifier instead of the warm liquid refrigerant from the condenser, the latent heat of vaporization of the condensing vapors in the condenser coil 27 is a cooling medium in said condenser, with-- drawing a mixture of uncondensed gases and vapors from said condenser, bringing the withdrawn gaseous mixture and portions of the cold liquid refrigerant of the system into indirect heat exchange relation so that the vapors in the gaseous mixture are further condensed and the liquid refrigerant is heat ed and partially vaporized by the heat in the gaseous mixture, and separating said vaporized refrigerant from less volatile ingredients in said liquid refrigerant and returning said vaporized refrigerant to be again used in the refrigeration method. r

2. The method of refrigeration which includes compressing the vapor of a liquid refrigerant, passing the compressed vapor through a condenser in a direction opposite from the top of an ascending passage in said condenser, bringing the withdrawn gaseous mixture and portions of the cold liquid refrigerant of the system into indirect heat ex-' change relation so that the vapors in the gaseous mixture are further condensed and theand separating said vaporized refrigerantfrom less volatile ingredients in said liquid refrigerant and returning said: vaporized re-,-

frigerant to be again used in the refrigeration method.

3. The method of refrigeration in which the vapor of a volatile liquid refrigerant is compressed and condensed, comprising the following steps, causing the.\ refrigerant vapor to ascend in a substantially upright column of substantialheight while being condensed by a condensing medium flowing in a counter current direction whereby non-condeusible gas mixed with the vapor tends to separate from the vapor in said ascending column under the influence of gravity and rise to an overhead outlet, withdrawing the I gas and dense vapor through said outlet,"and subjecting the withdrawn gaseous mlxture to the cooling action of the liquid refrigerant to mixture.

further condense the vapors from'lthe gaseous 4. The method of refrigeration in which.

the vapor of a volatile liquid refrigerant ;is. compressed and condensed, comprising the following steps, causing the refrigerant vapor after partial cooling to flow in-an ascending direction while being further condensed,

whereby non-condensible gas mixedwith vapor tends to separate from the dense vapor Y insaid ascending column under the influence of gravity and .rise to an overhead outlet, withdrawing the gas and dense vapor through said outlet, and subjecting the withdrawn gaseous mixture to the indirect coolingaction of a portion of the liquid refrigerantso that the remaining vapors in the gaseousmixture are condensed from the uncondensible gases and the liquid refrigerant is partially vaporized by the heat in the gaseous'mixture, and separating and recovermg said vaporized refrigerant from lcssvol' atile ingredients in saidliquid refrigerant.

5. In a refrigeration apparatus, "the com bina't on w1th a compressor,condenserjand' from the uncondensible gases, and the re.

frigerant liquid is also partially vaporized, and a vapor return passage connecting said chamber with a low pressure portion of the refrigeration apparatus whereby said vaporized refrigerant is separated from less volatile impurities.

6. Ina refrigeration apparatus, the combination with a compressor, condenser and evaporator, of-a supplementary condensingelement, means for withdrawing uncondensed refrigerant vapors and gases". from said condenser and passing same through said condensing element, a container associated w,ith's'aid condensing element, a stand pipe connected with the bottom of said contamer, and means for supplying relatively cold liquid refrigerant from the refrigerant circulating portion of the apparatus tosaid stand ipe so that said container fillswith the re ativel cold refrigerant liquid to a level determined by the li uid in the stand pipe, and the vapors in sai condensing element are condensed from the uneoxidensible.

by indirect cooling, and th'e'refrigerant iquid is partially vaporized and separated as-avapor from its impurities.

7. In a refrigeration apparatus, the coinbination with a' com ressor: condense and evaporator, of'a condensing element, means for \vithd rawing imcondensed refrigerant vapors and gases "front'said condenser' and passin same througlrsaid condensing element, '-'on'l"a|ner associatedjwith-isald condens-iiigclcineut,}'a stand pi pe connected with 'the'bottoln of "said container, and a"val've=beween said stand l-p'ipc and; mar container :14 l a )ted to reventback flow, of liqu idfil'bm sa i d m intainer-"to said stand pipe: said=-stand pl 1 1e hei n g arranged to"reccivei'elati'vely cold liquid refrigerant from "the reffii'g semi;

culating portion of theapparatus a1 l' 'de-xf liver the same to said container to it" tel-mined level so that the refri 'eran are condcnsed'from the un'coii ensible by indirect cooling'and so that the ief liquid is partially vaporiZe'd-"amt' s" as a'vapor from its impurities:-

8. In,-a refrigeration apparatus; bina'tion with a compressor," condenser E and evaporator, of a condensing element," mfea'ns for withdrawing uncondens'edrefrigerant rapors and gases ,from saidcondenserind passing same through said condensm 'element, .a contameriassociated with sai condensing element, a'stand pipe inside said evaporator adapted to receive llquid'refrigerant from" said 'evapor'ator'a'nd deliver said liquid into said container, ava'por pipe'connected between the upper portion of sand container and a low pressure portion of the refrigeration apparatus, and arestricted opening in said vapor pipe adaptedto regu-v late the vapor pressure in said container. 9. Ina, refrigeration apparatus, the combevaporator, of a condensing element, means for withdrawing uncondensed refrigerant vapors and gases from said condenserand passing same through said condensm element, a container associated with sai condensing element, a 'stand' pipe inside said evaporator ada ted to receive li 'uid'refrigevent from sai liquid into said. container, a screen at-the top of said stand pipe adapted to prevent splashin of liqui from said stand "pipe into sai .evaporator,'and'a vapor pipe connecting the upper portion of said container with said fevaporator, the liquid refrigerant "in said container being adapted-to condense the vapors in'the condensing element from the "uncondensible gases by indirect cooling and being also adapted to be partially vaporized and se )arated as a vapor from the impurities in sai liquid refrigerant. i

10'. In a refrigeration apparatus, the combination with a compressor, condenser and evaporator,'of a con ductor between said condensing element and said condenser, a check valve in said con: ductor, means adapted to cause a partial "vac uum in said condensing element so as to open ensing'elem'ent', a con nation with a compressor, condenser. and

evaporator and eliver said are condense from the 11. In a refrigeration apparatus,

-= ,r,ef rigerant vapors and I denser and through said condensing element,

a container associated by indirect cooling and ant liquidis partially vaporized and separat ed as a vapor from itsimpurities.

bination with, a compressor, condenser and evaporator, of acondensing element means vapors and gases for withdrawing uncondensed refrigerant from sa1d condenser and passing same through said condensin elemerit, a container associated with sai com densing element, an open-topped-stand "pipe in'said evaporator connected with the bottom of said container, an overflow pipe in said evaporator adapted irigerant from said evaporator nto said stand pipe so that said container fills with said liquid to a level determined by' the liquid in said standpipe, said liquid in said container being adapted .to condense the varated as a vapor from "its heat in the vapors a compressor a por to said'condenser, a ated with said condenser cause the refrigerantvapor to ascend A 5 I .ing "element i height past sai ,the direction of flow ."to permit non-condensibl'e .the' influence I of gravity, "ment arran 13.Inare pors from the uncondensible gases .m-said condensing element and said liquid beingalso rized and sepaadapted to be partially va impurities by the 'in said "condensing elem n c 1 12. In a refrigeration apparatus,

from said evaporator and'discharge-said vacooling eoil associthe' refrigerant vapor,

a Lsubstantially up right paxage in' said condenser, adapted to in a 'u right coil inadirection'op 'te to of aid and e n from the refrigerant vapor under a" condensing eleseparate to receive sage and condense the refrigerant vapor from and means for. cooling said condensb the liquid .refrig erant.-

grigeration apparatus, the com.-

bination of a main condenser, an evaporator,

a compressor adaptedfto withdraw vapor from said evaporatorand discharge said va-" por to said condenser, a plurality of cooling coils associated with said condenser for con den'sation of the refrigerant vapor, means for causing the mixed-vs or gas-to ascend ina'su andnon-condensible umn or substantialheight ins'aid condenser i andtherebytend toseparate underZ-the action of gravity' cause the'refrigerant vapor to from -noneon dens'ible gases,

the c m to discharge liquid re-' lng refrigerant llqllld m'sald chamberjfor partially;

during the operation of, the

the combmat1on of a main condenser, an evaporator, apted J to withdraw=- vapor for condensation of Y 4 the mixture of and vapor rom theupper part of said pas-- refrigerant liquid in nected with the ntially upright col-- p a condensing element" arranged to rece1ve -.a mixture of gasesand vapor from-the upper part of sa1 d condenser to which said column ascends and condense the refrigerant-vapor from said gas,

and means for coo ng said condenser element by;the liquid refrigerant. 1 v V "14. In a refrigerationapparatus, the combination with a condenser, compressor and evaporator, of "ajchamber; means. for heating refrigerant'liquidinsaid chamber for par- 't-ially vaporizingithe liquid, a restricted-'va gor outlet for said chamber, and meansfor elivering liquid refrigerant tojsaid chamber during the operation of the apparatus and regulating the level of liquid in said chamber in accordancewith the diiference in pressure of the entering liquid and the vapor pressure in the chamber; v p a 15. In a refrigeration apparatus, the combination with a condenser, compressor and evaporator, of a' chamber, means for heat vaporizing'the liquid, a restricted v9. or outlet for said chamber, means-for de ivering liquid refrigerant to said chamber apparatus, hav mg )ifOVlSlOIl' for .predetermimng the pres sure "eadof the entering liquid, and a valve which controls the delivery, oflthe 11 said chamber and operates under the control of said 1i 'uid-headrand thevapor pressure 1n saidcham r.'-

a 16. In a refrigeration apparatus, the combination' a'icondenser, compressor and evaporator, of a chamber means for heating refrigerant liquid in said-chamber for partlally vaporizin' theliquid, a restricted vapor ,outlet for said 0 amber,-a stand pipe open at its upperiportion through erantis elivered from the refrigerant to circulating portion of the apparatus to said chamber, and-a valve which controls the liquid passage between the standpipeandsaid chamerand operatesin accord encein pressure of t e liquid in the stand pipe and thevapor r "in said chamber. a 17. In are ration apparatuathe eombination with a compressor, condenser and an evaporator,- of a chamber means chamber for parthe liquid, a stand ipe conttom of said cham r, and means for supplying li uid refrigerant from the refrigerant circulating Egretus to said-stand pipe so that said chamfills with there -rant liquid to alevel determined by the liquid-in the stand p1 and -a vapor return passage from sald'cham r to a low pressure portion of, the refri tion ap-j 125 paratus,'whereb the refrigerant hqmd is par- 1 tially vaporized and separated as a vapor from its impurities.

tially vapo bination with a compressor,

'quidfto 95 v i which liquid refrig- '105 ance with the difiery for heating portion ofv the ap--1. 20.

evaporator, of a chambenmeans for heating refrigerant liquid in said chamber for partially vaporizing the liquid, a stand pipe connected with the bottom of said chamber, and a valve between said stand pipe and said chamber adapted to prevent backflow of liquid from said chamber to said standpipe, said a stand pipe being adapted to receive liquid refrigerant from the refrigerant circulating portion of the apparatus and deliver the same to said chamber to a predetermined level, and a vapor return passage from said chamber to a low pressure portion of the refrigeration apto recelve liquid refrigerant from the evapo- I rater and deliver said liquid into said chamber, a vapor return pipe connecting the upper portion of said chamber with a low pressure portion of the refrigeration apparatus, and a restricted opening in said vapor return passage.

20. In a refrigeration apparatus, the (30111- bination with a com ressor, condenser and evaporator, of a rectlfying chamber, means for heating refrigerant liquid in said chamber for rectifying the liquid,.a stand pipe inside of-the evaporator connected with the lower portionof said chamber and adapted to receive liquid refrigerant from the evaporator and deliver the liquid 'into said chamber, a valve which controls the delivery of liquid from said stand pi e to said chamber and is I controlled by the differential pressures of the head of liquid in the stand pipe and'the vapor pressure in said rectifying chamber, and a vapor return passage connectlng the upper portion of said chamber with said evaporater.

WILLIS H. CARRIER. 

